The present invention is related to a biocompatible low modulus high strength titanium-niobium alloy, and in particular to a biocompatible Tixe2x80x94Nb alloy having a major phase of xcex1xe2x80x3 suitable for making a medical implant.
Titanium and titanium alloys have been popularly used in many medical applications due to their light weight, excellent mechanical performance and corrosion resistance. The relatively low strength commercially pure titanium (c.p. Ti) is currently used as dental implant, crown and bridge, as well as denture framework. With a much higher strength than c.p. Ti, Ti-6Al-4V alloy has been widely used in a variety of stress-bearing orthopedic applications, such as hip prosthesis and artificial knee joint. Moreover, the lower elastic modulus allows the titanium alloy to more closely approximate the stiffness of bone for use in orthopedic devices compared to alternative stainless steel and cobalt-chrome alloys in orthopedic implants. Thus, devices formed from the titanium alloy produce less bone stress shielding and consequently interfere less with bone viability.
Various attempts at providing low modulus, high strength titanium alloys for making medical implants with less stress shielding have been proffered by the prior art. There is still a need in the industry for a lower modulus and higher strength titanium alloys. In addition, studies have reported that the release of Al and V ions from the medical implants might cause some long-term health problems, for example the low wear resistance of Ti-6Al-4V alloy could accelerate the release of such harmful ions. Therefore, a titanium alloy free from potential harmful components is also an important goal of the present invention.
The present invention provides a biocompatible low modulus high strength titanium-niobium (Tixe2x80x94Nb) alloy containing xcex1xe2x80x3 phase as a major phase and consisting essentially of 10-30 wt % of Nb, preferably 13-28 wt % of Nb, and the balance titanium.
The Tixe2x80x94Nb alloy of the present invention may further comprises one or more incidental impurities selected from the group consisting of carbon, oxygen and nitrogen, wherein a total amount of said one or more incidental impurities is less than 1 wt %.
The present invention also discloses a medical implant made of the titanium-niobium alloy of the present invention.
Preferably, the medical implant of the present invention is an orthopedic implant.
Preferably, the medical implant of the present invention is a dental implant, dental crown, dental bridge or a denture framework.
The present invention further provides a method of treating a patient requiring bone or dental prosthesis comprising implanting the orthopedic implant or dental implant of the present invention into said patient.